"There are 620 students at the school and there's only one of me," says Brabble, just a few days after one of his counterparts, a school-based police officer in San Diego, Calif., disarmed a school shooter who was a senior.

So in response to a rash of violence in American schools, he did what more and more adults are doing: He enlisted students not just as hallway watchmen, but actual problem-solvers and preachers of positive vibe.

From the Assets Middle School in Honolulu, Hawaii, to Cape May (N.J.) Middle School, teachers and principals are tapping student ingenuity, idealism, and brashness to reduce tensions and even inform officials about brawls that are brewing. Indeed, a new breed of front-line student activists is reshaping the debate over how to help maladjusted peers.

Moreover, preliminary studies and anecdotal evidence show that these student activists are making a difference.

"Incidents of violence are dropping at schools that have positive safe-school planning going on," says Carleen Wray, assistant director of the Center for the Prevention of Violence here in Raleigh.

Many schools are still relying on "get-tough" programs that popped up in the 1990s to target potential troublemakers. But educators increasingly acknowledge that suspension policies and campus officers may not be enough - and that students often know more than they let on about classmates who turn violent.

Based in Raleigh, Students Against Violence Everywhere (SAVE) has become a major player in the antiviolence movement, spreading from the Piedmont like wildfire since the 1999 Columbine shootings. SAVE has grown to 680 chapters in 34 states today, from seven chapters around Charlotte, N.C., in 1993. Nearly 80,000 kids are involved, and student committees help create the materials that are distributed to chapters.

"More and more students, now in the wake of the San Diego shootings, are willing to cross the threshold and break that code of silence," says Ron Stephens of the National School Safety Center in Westlake Village, Calif. "They ultimately understand that it's for the good of the perpetrator, and for their own safety."

Educators at Northern High School in Durham, N.C., have found the responsiveness they're looking for in Roba Ghanayem, Wes Blalock, Lindsay Whitaker, and Lisa Bland, officers of the school's eight-year-old SAVE club. The upperclassmen aren't worried about being pegged as geeks or do-gooders. They take their charge seriously, but also try to make club membership fun.

Adults are often impressed with their courage. Lisa, for one, uses her quiet demeanor to glean rumors from her classmates. At the first sign of trouble, she informs the school resource officer.

"I don't care," she says confidently. "If someone tells me something's going to happen, they know I'm going to go right to the school officer and tell him about it. In fact, that's usually why they tell me, so they won't get beat up for it."

For Wes, SAVE's most effective role is outreach. Members perform a series of skits at local elementary and middle schools and the YMCA.

At a recent show, they gave the middle-schoolers a real scare: Two conspirators started a loud, fake fight in the middle of the assembly; then students were guided in a discussion.

The club also holds dances where everyone has to sign a "nonviolence pledge." And SAVE helps with peer-mediation sessions after girlfriends have been jilted or egos wounded.

"I'm finding, at least, that a lot of students are learning how to deal with their emotions, and that petty arguments don't seem to be escalating as much as they once did," Roba says.

Roba says SAVE is cutting a sharper profile on the heels of repeated school shootings. "Now when something happens in school, everybody starts asking, 'What's SAVE going to do?' "

Without question, its stock is rising: At Northern High School, the SAVE chapter finally got a room of its own, even if it was a decrepit wrestling locker room. But with space at a premium, it was a solid gift. With a couple of fundraisers, they turned it into a welcoming headquarters.

SAVE is perhaps the largest among many student-led antiviolence groups - from Teens Against Gang Violence in Dorchester, Mass., to the National Peer Helpers Association in Greenville, N.C. Even SADD, which used to stand for Students Against Drunk Driving, has gotten in on the trend. Now the acronym stands for Students Against Destructive Decisions.

To many, though, SAVE has special appeal. It was formed at West Charlotte High School in 1989 after Alex Orange, a well-known peacemaker, was shot for standing up to some youths from another school who were crashing an off-campus party.

The next Monday, hundreds of students and parents assembled to talk. Some wanted retribution. Instead, they channeled their energy into a more positive response and formed SAVE. Even today, the group's main color is orange.

As if to reaffirm their new responsibilities, these groups hold summits. At the 6th Annual SAVE Summit in Raleigh recently, attendees tackled everything from conflicts in the classroom to violence in people's homes. "We try to help show students that there are triggers that set off behavior, and there are ways to control those triggers," says Pam O'Riley, SAVE's executive director.

Still, critics wonder why, if these programs are so successful, the violence continues.

"It's true that we can't measure how well this is working," Wes says. "But at least we're out here honestly trying to do something about it. And, personally, I think it's definitely calmed the tensions."

One place to look for evidence is King's Mountain (N.C.) Middle School, where fights were becoming more numerous.

After starting a SAVE chapter, the school tried a new tack: If there were no fights for two weeks in a row, school would let out five minutes early. Things went well the first two weeks. Then, a fight broke out in the cafeteria.

In the past, students would have rushed around to cheer. This time, they stayed in their seats and booed the pugilists.